Researchers analysed information from more than 12,000 children born across the UK in 2000-01 who are being followed by the Millennium Cohort Study. They looked at a range of factors associated with mental illness and wellbeing at age 11.

While there was little evidence that coming from a better-off family led to greater wellbeing for the children, there was a clear relationship between household income and mental illness. The richer the family, the less likely the children were to display emotional and behavioural problems symptomatic of mental ill health, such as often being worried, unhappy and having temper tantrums.

In fact, there were few factors that affected mental illness and wellbeing in the same way, suggesting that these aspects of overall mental health are driven by very different things.

The study’s authors warned mental health practitioners, policymakers and other researchers against conflating the two concepts: “It is often assumed that when wellbeing decreases, mental illness increases. These findings suggest it is not so straightforward,” explained Dr Praveetha Patalay, the lead author. “there is little overlap in the risk factors associated with these two domains of mental health, suggesting that interventions aimed at reducing symptoms of mental illness may have little effect on improving wellbeing, and vice versa.”

Eleven-year-olds with communication difficulties, special educational needs, or chronic physical illness had more symptoms of mental illness than those who did not have these problems. However, none of these factors were related significantly to their wellbeing.

Girls had greater mental ill-health than boys, but were no more or less likely to have better wellbeing. This latter finding is contrary to what is normally seen among adults – women tend to have higher wellbeing than men as they get older.

Children’s relationships were very important for their mental health, but again mental illness and wellbeing were affected in different ways. For example, children who argued with their parents had lower wellbeing, but the negative effect on mental illness was 10 times greater.

Eleven-year-olds who reported being bullied by their siblings had slightly lower wellbeing and slightly more symptoms of mental illness that those who were not bullied at home. School bullying, on the other hand, had an effect four times greater than sibling bullying – but was only significant for wellbeing.

Schools and neighbourhoods played an important role in children’s wellbeing. Those who enjoyed and were engaged with school had significantly higher wellbeing than their peers. Similarly, those who felt safe in their local areas tended to have greater wellbeing. Schools and neighbourhoods did not influence the children’s risk of mental illness.

Notes to editors

Children’s wellbeing at age 11 was determined by asking them how satisfied they were with different areas of their lives, including school, family, friends, school work, their appearance, and their lives in general.

At age 11, parents were asked whether their child displayed a range of emotional and conduct problems that are known to be symptoms of mental ill health, including often being worried, unhappy and having temper tantrums.

The researchers considered 36 potentially associated factors in their analysis, including individual characteristics, family socioeconomic circumstances, family and home life, parent and child health, children’s relationships, and their wider school and neighbourhood environments.